Low cost single-step purification of endoglucanase from Aspergillus fumigatus ABK-9.

Low cost agro-waste was used as adsorption support for single-step purification of endoglucanase from the culture filtrate of A. fumigatus ABK-9. Among various agro-waste substrates, 1% NaOH pretreated rice bran was proved to be the best for adsorbing about 74.8 and 71.1% of endoglucanase at 4 °C and 10 °C respectively. Langmuir type adsorption isotherm at 4 °C showed maximum adsorption of enzyme at pH 5.0, which was in the range of optimum pH of the enzyme. The rice bran column bound enzyme was maximally eluted by a mixture of acetate buffer (0.05 M, pH 5.5) and ethanol (40%, v/v) at a ratio of 3:2 and a flow rate of 1 mL/min. A 5.52-fold purification of the enzyme was achieved from culture supernatant. The specific activity and recovery yield after purification were 294.0 U/mg and 40.15%, respectively, which were comparable with other contemporary protocols. The homogeneity of the enzyme was tested through sodium dodecyl sulphate polyacrylamide gel electrophoresis and a single band of 56.3 kDa was observed. Zymogram analysis finally confirmed the occurrence of endoglucanase in the single band.

Exploitation of fermented shrimp-shells hydrolysate as functional food: Assessment of antioxidant, hypocholesterolemic and prebiotic activities.

In the present study the bioactivities of chitooligosaccharides of fermented shrimp-shell hydrolysate (SSH) in respect to hypocholesterolemic, antioxidant and prebiotic activity were tested in male albino rat. Rats were treated with four different diets, viz., (i) cholesterol-rich (5%) basal diet (ChB), (ii) ChB+10% chitin, (iii) ChB+10% SSH and (iv) control group (without cholesterol). After 4 weeks of treatment, body mass index, liver weight, serum total cholesterol and LDL-cholesterol in groups (ii) and (iii) were decreased significantly than group (i). SSH supplementation significantly resists oxidative stress by reducing the thiobarbituric acid reactive substances and by increasing catalase, superoxide dismutase and free radical scavenging activity. The colonization of Lactobacillus and Bifidobacterium population in small and large intestine were more in group (iii) than other groups. Reduction of Clostridium perfringens population and non-significant changes of E. coli was also noted in SSH supplement group. Histological study revealed that the villus height and villus:crypt of the small intestine were increased significantly in SSH supplemented group (iii) without any diarrheal symptoms. The results demonstrated that the shrimp-shells hydrolysate has hypocholesterolemic effect, can resist lipid peroxidation and can influence the growth of health beneficial microbes, hence can be used as functional food for hypercholesterolemic patients.

Effect of newly isolated Lactobacillus ingluviei ADK10, from chicken intestinal tract on acetaminophen induced oxidative stress in Wistar rats.

The total antioxidative activity of L. ingluviei ADK10 isolated from chicken intestine intact cells and cell free culture supernatant (CFCS) was 54- 67.95%. The ability to scavenge a,a-Diphenyl-b-Picrylhydrazyl free radical ranged from 71 and 64% in intact cells and CFCS respectively. Total reducing activity of bacteria was equivalent to 290 µM/L of cysteine. Reducing glutathione activity was equivalent to 93.95µg/mL. Oral administration of the strain at a dose of 109 cfu/kg body weight to acetaminophen induced oxidative stress in rats increased catalase, glutathione and superoxide dismutase activity in the blood, liver and kidney and lowered malondialdehyde level. The results indicate that L. ingluviei ADK10 has potential free radical scavenging activity for the treatment of oxidative stress related disease.